As crypto-currencies increase in value, so does the payout from mining them. This creates a substantial economic incentive to not only deploy more mining hardware, but to also develop faster, more efficient mining hardware. We saw this with bitcoin: Mining migrated from CPUs, to GPUs, to FPGAs, and now to ASICs [1]. Today, Ethereum GPU mining is the norm, but the miners haven’t made the jump to running the ethereum mining/hashing algorithm, ethash, on specialized hardware solutions (e.g. FPGAs and ASICs). Plenty of articles and forums attribute this to ethash being memory hard (a.k.a. memory bound). Here, I’ll walk through where Ethereum mining’s memory hardness comes from, and what the next generation of custom ethereum mining hardware might look like. For this article, I’m assuming readers have a general understanding of standard computer technologies and crypto-currency blockchains, but don’t need to be programming or mining experts. For a more technical, programmer-oriented explanation of Ethereum’s mining algorithm, called ethash, please refer to the ethash page on the ethereum wiki. For a less technical introduction to blockchains, visit the blockgeeks blockchain guide here.